I. Technical Field
This invention pertains to telecommunications, and particular to operation of a network comprising base stations which communicate over an air or radio interface with wireless receivers.
II. Related Art and Other Considerations
In a typical cellular radio system, wireless user equipment units (UEs) communicate via a radio access network (RAN) to one or more core networks. The user equipment units (UEs) can be mobile stations such as mobile telephones (“cellular” telephones) and laptops with mobile termination, and thus can be, for example, portable, pocket, hand-held, computer-included, or car-mounted mobile devices which communicate voice and/or data with radio access network. Alternatively, the wireless user equipment units can be fixed wireless devices, e.g., fixed cellular devices/terminals which are part of a wireless local loop or the like.
The radio access network (RAN) covers a geographical area which is divided into cell areas, with each cell area being served by a base station. A cell is a geographical area where radio coverage is provided by the radio base station equipment at a base station site. Each cell is identified by a unique identity, which is broadcast as system information in the cell. The base stations communicate over the air interface with the user equipment units (UE) within range of the base stations. In the radio access network, several base stations are typically connected (e.g., by landlines or microwave) to a controlling node such as, for example, a radio network controller (RNC). The radio network controller, also sometimes termed a base station controller (BSC), supervises and coordinates various activities of the plural base stations connected thereto. The radio network controllers are typically connected to one or more core networks.
A radio access network (RAN) may have or include an Operation SubSystem (OSS), Network Manager, or the like. These entities may be employed to configure and administer the radio access network (RAN).
One example of a radio access network is the Universal Mobile Telecommunications (UMTS) Terrestrial Radio Access Network (UTRAN). The UMTS is a third generation system which in some respects builds upon the radio access technology known as Global System for Mobile communications (GSM) developed in Europe. UTRAN is essentially a radio access network providing wideband code division multiple access (WCDMA) to user equipment units (UEs). The Third Generation Partnership Project (3GPP) has undertaken to evolve further the UTRAN and GSM-based radio access network technologies.
The base stations comprising all or part of a radio access network can be considered as a radio base station network. Conventionally such a radio base station network comprises a rather homogeneous group of radio base stations or nodes. The radio base stations may be homogeneous in the sense of having a common structure and operating methodology. But even if there may be some variance in structure and operation, the radio base stations are (and are expected to be) homogeneous in terms of availability, e.g., same or similar capabilities and potential performance necessary for achieving a same level of availability to users and to the network.
The essentially homogenous nature of contemporary radio base stations imposes a significant and unnecessarily high cost for the radio base station network. For example, in view of their homogenous nature, all radio base stations require battery backup. In some cases, provision of battery backup for a radio base station costs as much as the radio base station itself. As another ramification of homogeneity, all radio base stations are deemed the same in terms of redundancy, hot swapping capability, and the like. Homogeneity also requires that all radio base stations be operated with power-on at all times, even in low-traffic time periods.
Urban wireless telecommunication networks are typically planned for capacity, such capacity being expressed in terms of ERLANG/area or cell-edge services. Most wireless telecommunication networks are initially installed or “rolled out” with a few radio base stations for coverage, and then (e.g., as demand for service grows) the capacity is increased by means of cell-split, e.g., splitting an initial cell served by an initial base station so that the initial base station subsequently handles only a portion of the cell, while the remainder of the initial cell is subsequently handled by a new base station.
As would be expected from the prevailing perspective of homogeneity for radio base stations, the state of the art is to have all radio base stations handled equally.
Moreover, the radio base station network does not take any action inconsistent with homogeneity when a radio base station is taken out of service. In a best case, the operating subsystem (OSS) of the radio access network (RAN) determines which radio base station is removed from service and why.
A radio base station may fall out of service for many reasons - planned or unplanned. A first such example reason or scenario of radio base station is that the radio base station requires or undergoes service (such as a fan replacement, for example, in which service personnel turn off the radio base station).
A second example occurs when the radio base station has an internal failure. If the operator has purchased redundant hardware for the radio base station, the redundant equipment can be substituted and would indeed keep the radio base station in service, albeit with an expensive solution.
A third example occurs when the mains power (e.g. power mains) to the radio base station is cut or lost, i.e. the radio base station experiences a power outage. If the operator has purchased a battery backup, the radio base station can be kept alive at least for some time using battery power. But again, this is an extraordinarily expensive solution.
A fourth example occurs when the operator (network) chooses to turn off a radio base station for a reason such as lack of traffic. An operator may be motivated to turn of a radio base station to decrease the power consumption of the network, e.g. a cost savings measure.
In view of the homogeneity of the radio base station of a radio access network, optimal performance of the radio access network from a user or customer perspective essentially requires that all radio base stations have equal availability, e.g. battery backup, hardware redundancy, and essentially consistent up-times, to maintain service.
What is needed, therefore, and an object of the present invention, are one or more of apparatus, methods, systems, and techniques for dynamically and economically provisioning and tuning a radio base station network